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Masatoshi Shimizu

Publications and source records attributed to Masatoshi Shimizu.

16 recordsLinked to original sources
PubMed2006

Recurrent severe mitral regurgitation due to left ventricular apical wall motion abnormality caused by coronary vasospastic angina: a case report.

A 76-year-old man developed congestive heart failure due to severe mitral regurgitation after episodes of vasospastic angina. Echocardiography demonstrated left ventricular apical akinesis with ballooning and deformity of the anterior mitral leaflet becoming concave toward the left atrium. The acetylcholine provocation test induced diffuse coronary vasospasm in the distal segments of both right and left coronary arteries and reproduced severe mitral regurgitation. Follow-up echocardiography demonstrated decreased mitral regurgitation with ameliorated apical wall motion. Coronary vasospasm remained refractory to antivasospastic medications and severe mitral regurgitation relapsed 1 month after discharge. Mitral valve annuloplasty with a Carpentier-Edwards physio ring was performed, and no recurrence of mitral regurgitation was observed despite some episodes of vasospastic angina. We speculate that vasospastic angina and the resultant apical wall motion abnormality caused tethering of the mitral subvalvular apparatus, leading to inappropriate mitral coaptation and severe regurgitation.

Aged↗
PubMed2006

[Recurrent episodes of takotsubo-like transient left ventricular ballooning occurring in different regions: a case report].

A 62-year-old male with emphysema developed recurrent episodes of transient left ventricular ballooning occurring in different regions. Left ventriculography revealed symmetric mid-ventricular ballooning when he was 60 years old, and he also developed mid-ventricular ballooning of larger extent at the age of 62 years. Furthermore, as he was treated for severe asthma attack 3 months later, left ventricular apical ballooning occurred. Echocardiography also demonstrated akinetic wall motion in the right ventricular apex. These episodes showed myocardial infarction-like onset, ST elevations on electrocardiography, no significant increases in cardiac enzymes, wall motion abnormalities incompatible with coronary artery disease, and complete recovery within a few weeks. From these findings, we speculate that the recurrent left ventricular wall motion abnormalities including the mid-ventricular ballooning were so-called takotsubo-like left ventricular dysfunction.

Echocardiography↗
PubMed2005

Myocardial contrast echocardiography with 1.5-harmonic imaging in the diagnosis of cardiac malignant lymphoma.

We applied myocardial contrast echocardiography with 1.5-harmonic imaging to an atrioventricular groove tumor in a patient with malignant lymphoma. Contrast echocardiography initially showed one centric legion and some patchy echogenic foci within the tumor, all of which were indicative of arterial components. Subsequently, the tumor was enhanced homogenously, reflecting parenchymal hyperperfusion. These findings were consistent with previous observations of malignant lymphoma using color Doppler. We believe that myocardial contrast echocardiography could afford an important clue to the histologic diagnosis of cardiac tumors.

Aged↗
PubMed2005

Purification and cDNA cloning of NADPH-dependent aldoketoreductase, involved in asymmetric reduction of methyl 4-bromo-3-oxobutyrate, from Penicillium citrinum IFO4631.

Penicillium citrinum was found to catalyze the reduction of methyl 4-bromo-3-oxobutyrate to methyl (S)-4-bromo-3-hydroxybutyrate [(S)-BHBM] with high optical purity. From the strain, a cDNA clone encoding a novel NADPH-dependent alkyl 4-halo-3-oxobutyrate reductase (KER) was isolated. Escherichia coli cells overexpressing KER produced (S)-BHBM in the presence of an NADPH-regeneration system.

Alcohol Oxidoreductases↗
PubMed2005

Retrievable Günther Tulip filter complicated by sepsis and retroperitoneal hemorrhage: successful management by filter retrieval.

We encountered complications of septic shock and retroperitoneal hemorrhage which occurred after implantation of a retrievable Günther Tulip filter. A 79-year-old woman was diagnosed as right femoral vein thrombosis, and a retrievable Günther Tulip filter was deployed prior to a total knee replacement surgery. However, the patient developed septicemia due to Citrobacter freundii, followed by thrombocytopenia and retroperitoneal hemorrhage. A large hematoma was formed along the lateral side of the filter struts. We considered that the filter should be removed to control retroperitoneal hemorrhage and prevent secondary infection of the hematoma. Removal of the retrievable filter was effective in managing these complications.

Aged↗
PubMed2004

High diagnostic value of anticalpastatin autoantibodies in rheumatoid arthritis detected by ELISA using human erythrocyte calpastatin as antigen.

OBJECTIVE: To develop a quantitative method of measuring autoantibodies against human calpastatin in rheumatoid arthritis (RA) and to determine their diagnostic value compared with other autoimmune and articular diseases. METHODS: We performed a highly sensitive ELISA for IgG and IgM anticalpastatin autoantibodies in human sera using human erythrocyte calpastatin as an antigen. Samples were diluted 1:2000 for the measurement of IgG and 1:400 for IgM. RESULTS: IgG anticalpastatin antibodies were found in the sera of 48 of 58 patients (82.8%) with RA. In contrast, IgG anticalpastatin antibodies were found in the sera of only 2 of 11 (8.3%) patients with osteoarthritis (OA). Compared to sera from patients with other autoimmune diseases, anticalpastatin antibody sensitivity for RA was better than that of systemic lupus erythematosus (5.6%), systemic sclerosis (0%), mixed connective tissue disease (0%), and Sjögren's syndrome (20%). IgG anticalpastatin antibodies also showed high specificity (96.1%) for RA. Almost 90% of patients with RA were positive for IgG or IgM anticalpastatin antibodies. CONCLUSION: We have developed a simple, sensitive, specific, and quantitative ELISA for anticalpastatin antibodies that may have a high diagnostic value for RA.

Adult↗
PubMed2004

[Usefulness of dobutamine stress echocardiography in a patient with aortic valve stenosis and left ventricular dysfunction: a case report].

A 76-year-old man with previous antero-septal myocardial infarction and aorto-coronary bypass surgery developed exertional dyspnea. Echocardiography revealed diffuse left ventricular hypokinesis and aortic stenosis with a mean pressure gradient of 29 mmHg. Coronary angiography showed no significant lesions in the bypass grafts and total occlusions of the proximal left anterior descending artery and mid circumflex artery. Dobutamine stress echocardiography was performed to evaluate the severity of aortic stenosis and left ventricular functional reversibility. Administration of dobutamine increased the mean pressure gradients to 48 mmHg and increased the stroke volume by 28% without change in aortic valve area of about 0.5 cm2. We considered that our patient had severe aortic stenosis with contractile reserve. After aortic valve replacement, he improved with better left ventricular function.

Aged↗
PubMed2004

[Isolated left ventricular noncompaction in the elderly: a case report].

A 83-year-old man with an implanted pacemaker was admitted to our hospital for dyspnea. Echocardiography revealed left ventricular dilation and diffuse hypokinesis mimicking dilated cardiomyopathy. Multiple trabeculations and deep intertrabecular recesses were prominent in the apical and posterior walls. Computed tomography with contrast medium also showed prominent trabeculations. Thallium-201 and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid scintigraphy demonstrated fixed defects in the inferior wall. These findings were consistent with isolated noncompaction of the ventricular myocardium. The patient's symptoms of heart failure improved in response to treatment, including carvedilol. Isolated noncompaction of the ventricular myocardium is recognized as a rare congenital disorder of infancy with fatal outcomes, with some reports of cases in adults. The present patient is the most elderly described to date.

Aged↗
PubMed2003

Quantitative assessment of hand radiographs of rheumatoid arthritis: interobserver variation in a multicenter radiographic study.

We investigated interobserver variations in the Larsen radiographic scoring method on hand radiographs of rheumatoid arthritis (RA) patients in a multicenter trial and developed a new radiographic scoring method. Thirteen experienced rheumatologists scored 10 representative RA hand radiograms with the Larsen scoring method and clarified the precipitating factors of interobserver variation. Based on this study, it was proved that the ankylotic joint, overlapping joint, and more precise erosive joint are needed for optimal radiographic evaluation. Therefore, we modified the Larsen scoring method on the basis of these precipitating factors and developed a novel radiographic scoring method. Finally, to determine which scoring system was most reliable, the interobserver variation using three methods (original Larsen method, revised Larsen method, our scoring method) were compared by 13 experienced rheumatologists and 13 residents. Our scoring method proved to have simplicity, reliability, and ease of learning. These results suggest that our novel radiological quantitative assessment method has useful applications for clinical studies in patients with RA.

Arthritis, Rheumatoid↗
PubMed2003

Multiple coronary aneurysms resulting from isolated coronary vasculitis in an elderly patient.

An 81-year-old man developed multiple coronary aneurysms, including the left main truncus, that were unexpectedly found by coronary angiography. He had been followed-up for 14 years because of angina pectoris; his initial coronary angiograms in 1985 showed some stenotic segments but no aneurysmal changes. The patient died of gastric cancer in March 2000. On microscopic examination of the coronary arteries, the prominent feature was an inflammatory reaction in the medial layer, comprising chiefly small lymphocytes and plasma cells. The internal and the external elastic membranes were destroyed, presumably causing the aneurysmal dilatation of the vessels. There was a moderate degree of concomitant atherosclerotic fibrointimal thickening. No evidence of vasculitis was seen in sections of the aorta, peripheral arteries, and other major organs. The present case is unique because the cellular infiltrates were confined to the coronary media and although a definite diagnosis was not made, it was probably an atypical form of vasculitic disease; namely, isolated coronary vasculitis.

Aged↗
PubMed2003

Echocardiographic assessment of right ventricular obstruction in hypertrophic cardiomyopathy.

Echocardiography was used to evaluate the incidence, flow dynamics and morphological characteristics of right ventricular obstruction in 91 patients with hypertrophic cardiomyopathy. Color flow mapping was used to define the sites of obstruction in the left and right ventricles. Ventricular obstruction was considered to be present if the flow velocity was less than 2.0 m/s as measured by continuous wave Doppler. The thickness of both the right ventricular free wall and anterior ventricular septum was measured to assess the magnitude and extent of hypertrophy. Right ventricular obstruction was present in 14 patients of whom 6 (43%) had left ventricular obstruction also. The right ventricular obstructions were found in the outflow tract (9 patients), mid-base septal bulge (2 patients) and apical trabecular region (3 patients). Doppler waveform was confined to systole in all patients with obstruction in the outflow tract and in one of the patients with mid-base septal bulge. Moreover, the flow wave persisted into early diastole in 4 patients, including 2 with apical trabecular obstruction. The thickness of both the right ventricular free wall and anterior ventricular septum suggested that these hypertrophied regions were the sites of right ventricular obstruction. Thus, echocardiography was useful in evaluating right ventricular obstruction in hypertrophic cardiomyopathy.

Adult↗
PubMed2003

[Reversible left ventricular dysfunction manifesting as hyperkinesis of the basal and the apical areas with akinesis of the mid portion: a case report].

A 60-year-old man underwent emergent cardiac catheterization because of anterior chest oppression. He had been treated with calcium antagonist and nitrate. Coronary angiography showed no organic stenosis. However, left ventriculography revealed that the basal and the apical areas were hyperkinetic and the mid portion was akinetic. Echocardiography showed that the bizarre-shaped left ventricular dysfunction had completely recovered after a week. Serial electrocardiography demonstrated initial ST-segment elevation in the precordial leads followed by T-wave inversion in II, III, a VF and V4-V6. Coronary artery spasm provocation tests were negative. Endomyocardial biopsy revealed focal myocardial depletion and mild fibrosis. The present case may be an atypical form of tako-tsubo-like left ventricular dysfunction in which the left ventricular contraction is symmetric with both hyperkinetic and akinetic areas.

3-Iodobenzylguanidine↗
PubMed2002

Concomitant Cushing's syndrome due to adrenal adenoma in a patient with systemic lupus erythematosus.

A 51-year-old woman had been administered 5 mg/day of prednisolone due to systemic lupus erythematosus (SLE). She developed hypertension, hypokalemia and a pathologic pubic fracture during two years before admission. Although iatrogenic Cushing's syndrome was initially suspected, we diagnosed her as concomitant Cushing's syndrome due to a left adrenal tumor. The elevated endogeneous glucocorticoids were evaluated from urinary excretions of 17-hydroxycorticosteroids, which was 2-fold higher than normal and equivalent to 10 mg of prednisolone. After laparoscopic left adrenalectomy, SLE was favorably controlled with 15 mg of prednisolone, the dosage of which was equivalent to the estimated amount of preoperative glucocorticoids.

Adenoma↗
PubMed2002

Enhanced local production of osteopontin in rheumatoid joints.

OBJECTIVE: To investigate the involvement of osteopontin (OPN) in the pathogenesis of rheumatoid arthritis (RA), localization and production of OPN were examined in patients with RA. METHODS: Localization of OPN in the rheumatoid synovium was examined by immunohistochemistry. In vitro OPN production by cultured synovial cells from patients with RA (n = 5) and with osteoarthritis (OA) (n = 5) was assessed by ELISA. OPN concentrations in plasma and synovium were quantified in patients with RA (n = 23) by 2 distinct ELISA systems to measure both thrombin cleaved and non-cleaved OPN. The same experiments were done in patients with OA (n = 15) and healthy volunteers (n = 10) as a control. RESULTS: OPN was highly detected by immunohistochemistry predominantly in the RA synovial lining cells, while less and scattered OPN was detected in OA synovial tissues. ELISA revealed that cultured RA synovial cells secreted significantly more OPN than OA cells. ELISA also showed a marked increase of OPN levels in synovial fluid (SF) of patients with RA and with OA compared to the control plasma OPN levels, although OPN levels were not increased in RA and OA plasma compared to healthy controls. SF OPN levels of patients with RA were significantly higher than those of patients with OA, and correlated with serum C-reactive protein levels. The ratios of thrombin cleaved versus non-cleaved OPN were significantly increased in RA plasma and SF compared with OA plasma and SF and plasma from healthy controls. CONCLUSION: Our results revealed enhanced local production of OPN in rheumatoid joints, suggesting involvement of OPN in the pathogenesis of RA.

Adult↗